• Journal of The Korean Astronomical Society
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• v.38 no.2
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• pp.69-72
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• 2005

The FIMS (Far-ultraviolet IMaging Spectrograph; also known as SPEAR, Spectroscopy of Plasma Evolution from Astrophysical Radiation) is the primary payload of the STSAT-1, the first Korean science satellite, which was launched in September, 2003. The FIMS performs spectral imaging of diffuse far-ultraviolet emission with the unprecedented wide field of view and the relatively good spectral resolution. We present far-ultraviolet spectral observations of highly ionized interstellar medium including supernova remnants, superbubbles, soft X-ray shadows, and the molecular hydrogen fluorescent emission lines. The FIMS has detected He II, C III, 0 III, O IV, Si IV, O VI, and $H_2$ fluorescent emission lines. The emission lines arise in shocked or thermally heated and in photo-ionized gases. We present an overview of the FIMS instrument and its initial observational results.

• Journal of Welding and Joining
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• v.28 no.6
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• pp.40-44
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• 2010

Laser assisted machining (LAM) has been researched in order to machine the silicon nitride ceramics economically and effectively. LAM is an effective machining method by local heating of the cutting part to the softening temperature of the silicon nitride using laser beam. When silicon nitride ceramics is heated using a laser beam, the surface of silicon nitride ceramic is softened, oxidized and decomposed. And then surface hardness is decreased. Through machining in low viscosity and hardness conditions, silicon nitride was machined effectively and the life span of tool was increased. The plastic deformation was occurred due to softening of amorphous YSiAlON above $ 1,000^{\circ}C$. Transgranular fracture of ${\beta}-Si_3N_4$ was occurred when YSiAlON was not softened, but mostly intergranular fracture was occurred by the plastic deformation of softened YSiAlON.

• Journal of the Korean Chemical Society
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• v.13 no.1
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• pp.16-24
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• 1969

Ni, Co, Zn, Cd, Mn, Mg, Ca, Sr, Ba 등의2가 금속과 U(VI) 및 V(IV)의 이온이 만드는 $MCup_2$ 조성의 cupferrates 착화합물에 관하여, 그 용해도가 좋은 dioxane-$H_2O$, methanol-$H_2O$, ethanol-$H_2O$ 및 2-propanol-$H_2O$의 혼합용매를 사용하여, 그들의 몰분율을 변화시키면서 제 1, 제 2 및 전체의 열역학적인 안정도상수를 전위차적정법에 의하여 측정하고, 안정도 상수와 유기용매의 몰분율에 관한 실험식을 얻었다. 한편 분광광전법에 의하여 가능한 cupferrates의 전체 안정도 상수를 측적하여 이들과 비교하였다. 2가 금속 cupferrates의 안정도상수는 위에 적은 금속의 순서로 감소하고, 이들의 log $K_1$은 log $K_2$보다 크지만, U(VI)과 V(IV)의 cupferrates는 log $K_1$$K_2$여서 1:1과 1:2 착화합물 사이에 구조 변화가 있는듯하다. 몰분율이 영인 점에서의 안정도상수는 금속 cupferrates의 수용액에서의 용해반응의 평형상수에 해당하며, 금속의 착화합물의 안정도상수와 용해도와는 무관하고, K<$10^5$인 cupferrates에 관해서는 분광전법을 적용하기 어렵다.

• The Korean Journal of Pain
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• v.14 no.1
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• pp.76-82
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• 2001

Background: Postoperative nausea and vomiting (PONV) are common after general anesthesia and patient controlled analgesia (PCA) using opioids. This study was designed to compare the effectiveness of ondansetron plus dexamethasone versus ondansetron alone in the prevention of PONV in a patient undergoing a PCA. Methods: We studied 166 ASA I, and II in-patients undergoing general anaesthesia for major gynecological surgery. After induction of anesthesia, Group 1 (n = 64) received intravenous (IV) dexamethasone 10 mg and Group 2 (n = 102) received IV saline 2 ml before the surgical incision. Each patient received IV meperidine 50 mg as a loading dose. Meperidine 5 mg/kg, ketorolac 3.6 mg/kg and ondansetron 8 mg diluted in 40 ml solutions were connected to PCA pump for postoperative pain control. Mean arterial blood pressure, heart rate, pain score and symptom-therapy score were checked at 1, 4, 8, 16, 24, and 36 hours after the PCA connection. Results: For Group 1 and Group 2, respectively, the overall incidence of PONV was 12.5% and 23.5%. The pain scores were lower in patients receiving a combination of ondansetron and dexamethasone than those on ondansetron alone at 4 hr (P < 0.05), 8 hr (P < 0.05) and 16 hr (P < 0.05). Conclusions: This study suggests that the combination of ondansetron and dexamethasone is not more effective than ondansetron alone in the prevention of postoperative nausea and vomiting in women having PCA following major gynecological surgery but is more effective for pain control.

• Restorative Dentistry and Endodontics
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• v.18 no.1
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• pp.122-132
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• 1993

The aim of this study was to investigate the level of radiopacity of glass ionomer cements and to determine the optimum level of radiopacity that is the most compatible with the radiographic diagnosis of secondary caries. The experiments were performed in two parts. In the first part, the radiopacities of 9 glass ionomer cements (FI, FII, FI-LC, FII-LC, SI, SII, Vit, B-VLC, AC) and base materials(Ultra-Blend, Zinc phoaphate cements, Cavitec, Dycal) were measured by densitometer. Then all experimental materials were divided into 5 groups based on the level of radiopacity of enamel and dentin. In the second part, class III cavities with or without secondary caries were prepared in extracted anterior teeth. The representative materials of each group with different radiopacities were inserted into each cavity. The radiographs were interpreted by 15 dentists and seconsary caries were diagnosed according to a five-point confidence rating. Sensitivity and ROC analysis were used to compare observer performance. The following results were obtained : 1. The radipacity of glass ionomer cements varied between 1.111mm Al and 6.011mm Al equivalent. 2. Among experimental materials, three materials in group I had lower radiopacity than that of dentin. The radiopacity of two materials in group II slightly exeeded that of dentin. Three materials in group III had slightly lower radiopacity than that on enamel. The radiopacity of one material in group W was slightly higher than that of enamel. Four materals in group V had the radiopacity that exeeded over 2.0mm AI equivalent to that of enamel. 3. The group IV was the highest for sensitivity and the group V was the highest for ROC area. However, no significant differences were obtained among group II, III, IV and V (P<0.05) but only group I was significantly lower(P<0.01). 4. In comparison with the observer performance for the radiographic diagnosis of secondary caries, the group II, III, IV, and V were superior to the group I (P<0.01). And so the optimum level of radiopacity to detect the secondary caries was the radiopacity that is higher than that of dentin.

• KCID journal
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• v.14 no.1
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• pp.50-56
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• 2007

In this study, the Soil and Water Assessment Tool (SWAT) model was used to assess spatiotemporal effects on watershed runoff and sediment characteristics due to land uses changes from 1999 to 2002 at the small watershed, located in Chuncheon-si, Gangwon province. The annual average flow rate of Scenario I (long-term simulation using land use of 1990), II (long-term simulation using land use of 1996), III(long-term simulation using land use of 200) and IV(simulation using land use of 1990, 1995, and 2000) in long-term simulation) using the SWAT model were 29,997,043 m3, 29,992,628 m3, 29,811,191 m3 and 29,931,238 m3, respectively. It was shown that there was no significant changes in estimated flow rate because no significant changes in land uses between 1990 and 2000 were observed. The annual average sediment loads of Scenarios I, II, III and IV for 15 year period were 36,643 kg/ha, 45,340 kg/ha , 27,195 kg/ha and 35,545 kg/ha, respectively. The estimated annual sediment loads from Scenarios I, II, and III, were different from that from the scenario IV, considering spatio-temporal changes in land use and meterological changes over the years, by 10%, 127%, and temporal changes in land use and meterological changes over the years, by 10%, 127%, and 77%. This can be explained in land use changes in high soil erosion potential areas, such as upland areas, within the study watershed. The comparison indicates that changes in land uses upland areas, within the study watershed. The comparison indicates that changes in land uses can affect on sediment yields by more than 10%, which could exceed the safety factor of 10% in Total Maximum Daily Loads (TMDLs). It is, therefore, recommended that not only the temporal analysis with the weather input data but also spatial one with different land uses need to be considered in long-term hydrology and sediment simulating using the SWAT model

• Journal of Environmental Science International
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• v.23 no.5
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• pp.911-942
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• 2014

This study was carried out to investigate the flora of indigenous habitat of Donghae-si and Samcheok-si in Gangwon-do, Korea. The vascular plants were collected 18 times (from March to October 2011), and were identified as 804 taxa; 127 families, 445 genera, 720 species, 8 subspecies, 69 varieties, 5 forms and 2 hybrids. In the flora of this area, the calcicolous plants were 55 taxa; Cheilanthes argentea, Clematis serratifoliam, Quercus variabilis. Epipactis papillosa, etc. The endangered plants designated and protected by the wildlife protection law, the Ministry of Environment, Korean were counted to one taxon; Cymbidium macrorhizum. The red list of vascular plants according to IUCN valuation basis were examined, endangered species (EN); Prunus yedoensis and Cymbidium macrorhizum, Vulnerable species (VU); Juniperus chinensis, Pulsatilla tongkangensis, Diarthron linifolium and Swertia wilfordii, Near Threatened species (NT); Paeonia japonica, Allium senescens, Epipactis papillosa and Pogonia minor, Least Concern species (LC); Asplenium ruta-muraria, Platycladus orientalis, Monotropa hypopithys and Eleutherococcus divaricatus var. chiisanensis, etc., Data Deficient species (DD); Paeonia lactiflora var. trichocarpa, and Not Evaluate species (NE); Prunus choreiana, Panax ginseng and Polygonatum infundiflorum etc. Korean endemic plants of this area were 26 taxa; Aconitum pseudolaeve, Corydalis hirtipes, Vicia chosenensis, Salvia chanroenica and Hemerocallis hakuunensis, etc. The floristic regional indicator plants found in this area were 130 taxa comprising 11 taxa of grade V, 15 taxa of grade IV, 33 taxa of grade III, 15 taxa of grade II, 56 taxa of grade I. The naturalized plants were identified as 67 taxa and the percent of naturalized index (NI) was 8.3% of total 804 taxa vascular plants.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.22 no.6
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• pp.41-61
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• 2019

The purpose of this study was carried out to present the basic data for constructing a ecological stream, Shindangcheon stream located in Gyeongju-si, Gyeongsangbuk-do, South Korea. From August 2017 to June 2019, a total of 7 surveys were conducted. The numbers of vascular plants were summarized as 388 taxa including 75 families, 246 genera, 360 species, 4 subspecies, 19 varieties, 2 forms and 3 hybrids. The most families of taxa were Poaceae (59 taxa), Asteraceae (47 taxa), Fabaceae (27 taxa), Rosaceae and Cyperaceae (20 taxa, respectively), and Polygonaceae and Brassicaceae (15 taxa, respectively). The rare plant was Aristolochia contorta Bunge, and the Korean endemic plants were 4 taxa, such as Populus × tomentiglandulosa T.B.Lee, Salix koriyanagi Kimura ex Goerz, Lespedeza maritima Nakai, and Weigela subsessilis (Nakai) L.H.Bailey. The specific plants by floristic region found in this site were 13 taxa comprising 8 taxa of grade I, 4 taxa of grade III, and 1 taxon of grade IV. The naturalized plants were 73 taxa, such as Fallopia dumetorum (L.) Holub, Persicaria orientalis (L.) Spach., Potentilla supina L. var. ternata Pterm., and so forth. The invasive alien plants were 6 taxa, such as Rumex acetosella L., Sicyos angulatus L., Solanum carolinense L., Ambrosia artemisiifolia L., Lactuca serriola L., and Symphyotrichum pilosum (Willd.) G.L.Nesom..

• Journal of Embryo Transfer
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• v.31 no.4
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• pp.319-322
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• 2016

CD26, also known as Dipeptidyl peptidase IV (DPP-4), is a cell surface glycoprotein that belongs to the serine protease family and has wide spread organ distribution throughout the body. CD26 was previously characterized in immune cells but also has important metabolic functions which are not yet fully understood. Thus, we investigated the effect of CD26 in porcine parthenogenetic embryos. We attempted CD26 downregulation of porcine embryos by siRNA, and evaluated CD26 suppression of developmental competencies. Although the porcine embryos injected with CD26 siRNA were able to develop to the early stage, these embryos were decreased to form blastocysts. Our results indicated that CD26 is one of factors for the regulation of development of porcine embryos.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.13 no.9
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• pp.745-750
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• 2000

The (S $r_{0.85}$C $a_{0.15}$) Ti $O_3$(SCT) thin films are deposited on Pt-coated electrode (Pt/TiN/ $SiO_2$/Si) using RF sputtering method at various deposition temperature. The crystallinity of SCT thin films were increased with increase of deposition temperature in the temperature range of 200~500[$^{\circ}C$]. Also, the composition of SCT thin films were closed to stoichiometry (1.080~1.111 in A/B ratio). V-I characteristics of SCT thin films show the increasing leakage current with the increases of deposition temperature. The conduction mechanism of the SCT thin films observed in the temperature range of 25~100[$^{\circ}C$] can be divided into four regions with different mechanism by the increasing current. The region I below 0.8[MV/cm]shows the ohmic conduction. The region II between 0.9~2[MV/cm] is in proportion to J∝ $E^{1.5}$ , the region III between 2~4[MV/cm] can be explained by the Child’s law, and the region IV above 4[MV/cm]is dominated by the tunneling effect.ect.